1. Field of the Invention
This invention relates to multi-phase fluid flow meters and, in particular, multi-phase fluid flow meters capable of accurately measuring the flow of gas and liquid components of fluid flow over a wide range of fluid concentrations from high liquid voids, where the fluid to be measured is substantially void of liquid, to fluids including a substantial liquid component.
2. Discussion of Background
In the oil industry, it is often necessary to measure the output of oil wells under varying conditions. In particular, oil wells typically have fluid outputs including gas and liquid components, with the liquid components typically including water and oil. In order to reliably measure the quantity of each component in the oil well output, U.S. Pat. No. 5,099,697 discloses a multi-phase flow meter (MPFM) for measuring multi-phase fluid flow, and particularly three phase fluid flow including gas, water and oil. However, for oil wells which produce more than 97% gas by volume, it is very difficult to measure accurately the flow of each fluid component as the MPFM must be sized for the gas volumetric flow, while the liquid flow may be only a fraction of a percent. Under such circumstances which demand a wide operating dynamic range, accuracy over the entire range of operation, including the measuring of high void fraction fluids, i.e., high gas concentration fluids, is compromised.